According to this study published in the American Journal of Clinical Nutrition (and referred to in this medical news article), consuming tea with meals has a significant effect on iron absorption.
This study shows that tea consumed simultaneously with an iron-containing porridge meal leads to decreased nonheme iron absorption and that a 1-h time interval between a meal and tea consumption attenuates the inhibitory effect, resulting in increased nonheme iron absorption. These findings are not only important in relation to the management of iron deficiency but should also inform dietary advice, especially that given to those at risk of deficiency.
However, the same study reports that if tea is consumed an hour or more after the meal, the inhibitory effect of tea on iron absorption is attenuated. It is therefore recommended to have at least an hour gap between meals and tea
